I understand that you can't see what was so "off" about the post, but I could. I know The Bat! very well and Thunderbird slightly. Other than the comment about system resources, everything else stated about The Bat! was either wrong or a trivial criticism. So, yes - the 'facts' presented were not really facts, were certainly very "subjective" and thus, in my informed opinion, not worth keeping. Add to that, comments like "got sick of it" and "long live open source" are pointless and purely designed to antagonise.
You may also be unaware of the fact that I have previously had to remove other derogatory posts from "GOD00007 007" from elsewhere on the forum. So the feigned shock and surprise comments are also nothing more than a ploy to confuse you. Every forum gets them in the end - they are known on Usenet as "trolls".
As you have discovered for yourself, on the whole The Bat! is, and always has been more powerful than ThunderBird.
If you think that being misled by someone with an agenda to denegrate a powerful piece of work through innaccuracy in favour of (what may or may not turn out to be) their own opinion constitutes "a good attitude", then that is your choice. I disagree with that myself and would rather support you with accurate statements. You also have to bear in mind that this forum is web-indexed and I have no desire to see such wild exaggeration come up on a Google search for clear information about The Bat.
Please appreciate that I have clear instructions from the owners of this forum to remove any such wildly unfavourable, rude and ridiculing posts. You will also see many unfavourable but fair posts left exactly where they are scattered thoughout this forum.
Now. Back to the real conversation

There is a myth about opensource. That "it evolves quicker". Some projects certainly do proceed quicker, especially in the early stages. I use a lot of Opensource software myself. Most of it hasn't moved much (if at all) for 2 or 3 years in some cases. Others have trickled forward once they hit a peak. Also, the people on the projects can often change as they move into more professional pastimes. A major exception is The Gimp, which keeps getting better and better. FireFox doesn't seem to have progressed very far beyond the basic browser with a few security fix releases coming out after the main release, but it is certainly my browser of choice. Miranda-IM is my messenger of choice. VNC is my support software of choice.
There are a vast number of plugins being evolved for the FireFox project and that's where it moves rapidly. Thunderbird is likely to go the same way - in that you will have to rely on plugins from enthusiasts to cover the features you want to see covered. In the case of FireFox, many of my favoured / more complex plugins, particularly those that manage tabs better, have been evolved and then withdrawn when they started to conflict. Indeed, plugin conflict is a major bugbear in many of the Opensource programs I like.
By contrast, The Bat! is developed by a stable and committed team of talented programmers. It is their fulltime job to evolve this software and keep it ahead of the competition as best they can. I think they do a great job of that. The Bat! also has a 3rd party plugin community (not to the same scale as Thunderbird / Firefox, for sure) and a dedicated user group that evolve some excellent macro / filter sets (which extend the program functionality of themselves).
As for whether or not the Thunderbird address book will reach the sophistication of The Bat's - I wouldn't like to say. But I have my doubts that they will get there with the templates - The Bat's have already been evolved for 7 years and are wonderful for that. As for the template / address book integration - that's a whole new order of excellence and facility that I doubt you will even have had time to appreciate. Mass mailing using Quick templates. Quick templates with macros. Regular expressions to extract data from source mails.
If you'd rather judge the software in the light of the unwritten rules of this forum, then that's up to you. If you want to dismiss me as unhelpful and dismissive, again, that's up to you. I respectfully recommend that you browse this forum and (more importantly) the TBUDL archives to find out what kind of support there really is out there for The Bat!

In fact, if you were to communicate with the TBOT users mailing list on YahooGroups, you would find many ThunderBird / The Bat! cross users and get a far more accurate impression of the differences. Without fail, every one forced to use Thunderbird for its (currently) superior IMAP behaviour bemoans the loss of The Bat's Templates and address book. POP3 users tend to stay with The Bat! IMAP users are longing to come back.